Strain effect on the electrical conductivity of epitaxial La0.67Sr0.33MnO3 thin films

► Sr-doped LaMnO3 is the conventional cathode material used in solid oxide fuel cells. ► We utilized epitaxial thin films as a model system to systematically vary the amount of strain imposed by the underlying substrate. ► With increasing strain, the activation energy for small polaron hopping increases and the conductivity decreases by as much as an order of magnitude compared to the bulk material.